Device for preventing back drafts in fireplaces, stoves, and the like



March 3, 1931. 1,v MEYER 1,794,724

DEVICE FOR PREVENTING BACK DRAFTS IN FIREPLACES, STOVE'S, AND THE LIKE Filed July 29, 1929 Patented Mar. 3, 1931 UNITED STATES PATENT OFFICE ERNST AUGUST MEYER, OF HAMBURG, GERMANY DEVICE FOR PREYENTING BACK DRAFTS IN FIREPLACES, STOVES, AND THE LIKE Application filed July 29, 1929, Serial No.

'The object of the present invention is a device for preventing back draft of smoke in fire places, stoves, ovens, and the like. Hitherto this throwin back of the smoke has proved at times to e a ver great nulsance, and efi'orts have been ma e to remedy it by means of special chimney tops. Notwithstanding these means adopted, the nuisance has not been eliminated.

The resent invention however provides a device y means of which this nuisance is avoided, the device being inserted into the wall or partition by meansof a tubular or pipe like sleeve. The wind entering the chimney impinges on a specially shaped baffie plate, and is by it reversed in its direction of flow and turned in the direction of the natural draft in the chimney, and consequently entrains thesmoke in its owmdired tion and thus propels it out of the chimney instead of-into the room.

The drawing illustrates as an example only a constructional form of the device according to the invention.

Figure 1 is a vertical sectional view illustrating the invention in applied position in a chimney flue opening. s.

Figure 2 is an end view of the invention.

The invention, generally stated, includes a tapering thimble formed at its inner end with a battle consisting of a transverse vertical wall extending part way vertically from the lower inner end of the thimble and thenoutward at an oblique angle and then extended outward and upward! at an angle, with the edges of the inclined portions of the bafile inclined downward.

The device is formed with a substantially cylindrical-shaped side wall I), one end, however, being of greater diameter than the other end, thereby giving a slight tapered effect to allow for the insertion of the smaller end into an opening of a given diameter and to also allow a pipe 7' of the same diameter to be inserted in the larger end. Integrally formed with the side wall and partially covering the smaller end is a bailie plate a which extends diametrically across the opening for about one-third of its extent, then bent outward at an oblique angle for a like distance, and finalas1,9eo, and in se en January 5, 1929.

'ly bent still farther outward for a similar distance. The edges of the baflle plate are bent laterally, as shown at 0, to-increase the efliciency of the device. i

As shown, the device is inserted in a stove pipe opening in the wall e adjacent the vertical chimney d, with the smaller end outward, and with the open'section of the smaller end at the top. This top opening allows the passage of the hot products of combustion, while the entrance of the cool air coming down the chimney is blocked by the baffle plate. This plate not only prevents the entrance of the cool air, but reverses its direction, as shown by the arrows, and directs its force upward through the products of combustion, thereby greatly increasing the draft of the stove. A device of this character would not only increase the draft in stoves, but would prevent any back draft and would materially cool the products of combustion in the chimney, thereby lessening the dangers of fire. Such a simple construction could be easily made and easily installed.

What is claimed is 1. A stove pipe thimble comprising a substantially cylindrical-shaped section, one end being open, the other end being partially closed'by a plate integral with the side, said plate being bent upward and outward at the end to deflect the wind. I

2. A stove pipe thimble comprising a substantially cylindrical-shaped section, one end being open, the other end being partially closed by a plate integral with the side, said plate being bent upward and outward atthe end to deflect the wind, said bent-up plate covering substantially two-thirds the open end.

3. A stove pipe thimble comprising a substantially cylindrical-shaped section,.one end of said thimble being open, the other end having a plate integral with the side bent upward diametrically of the thimble for a portion of its extent. then bent outward for another portion and finally bent outward again, said part entirely covering the lower half of the thimble and directing the air impinging against it in an upward and outward direction to assist the products of combustion in escaping from the stove ipe.

4. A stove pipe thimble comprising a. substantially cylindrical-shaped section, one end being open, the other end formed with an integral, diametrically projecting and upstanding plate closing the lower part of said end, said upstanding plate being bent outward at an angle to the diametrically extending section of the plate and again bent outward at another point of the plate, the angle oi the last bend approaching the line of the axis of the thimble whereby the wind entering the stove pipe is deflected upward and outward to assist the products of combustion leaving the upper portion of the end of the thimble to escape to the atmosphere;

In testimony whereof I aifix my signature;

ERNST AUGUST 

